Cellulases the Shinier Look

In recent years, the use of cotton in garments has witnessed a revival. The higher comfort level of cotton fabric as compared to man-made fibers tilts the balance of customer favor towards cotton as the basic fiber in clothes. After many wash cycles, however, both the appearance and the soft feel of the cotton fabric are lost the surface appears bland and the fabric touch has turned rough. This roughness stems at least in part from loose ends of cotton fibers which have separated from the bulk fabric and stick out on the surface. To combat this phenomenon termed pilling, cellulases have been developed to preserve both the appearance and feel of cotton fabric during washing. 

An important parameter influencing the mode of action of cellulases is the accessibility of the cellulose to the enzymes. The molecular weights of cellulases range between 30 and 80 kDa. A comparison of the size of cellulase (3-8 nm) and the pore size of cotton swollen in water (1-7 nm) shows very clearly that cellulases can penetrate the cellulose to a limited extent only. In addition, the enzyme reaction takes place preferentially on amorphous cellulose because the more compact, crystalline cellulose structures do not offer any space for such macromolecules. Thus - provided of enzyme and process parameters have been selected correctly -cellulases act mainly on the textile surface. In this way interesting effects on cellu-losic fibers can be achieved. 

The machine is then opened to the air and oxidation occurs, thus restoring the indigo color and promoting uniform dye application, improved dye yield, and colorfastness. Such a process seeks to allow manufacturers to re-use dyebaths instead 

Cellulase enzymes break down the surface of the denim, thus releasing the indigo dye. The desired abrasion effect can be obtained totally without the use of purnice stones. 

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